Smart Metering Issues - Midwest Rural Energy Council · PDF fileSmart Metering Issues ... A Perspective on Radio-Frequency Exposure Associated With Residential Automatic Meter Reading,

Alfonso G. Tarditi

Electric Power Research Institute

52nd Annual Rural Energy Conference

February 12-14, 2014, La Crosse (WI)

Smart Metering Issues

2 © 2014 Electric Power Research Institute, Inc. All rights reserved.

Acknowledgments

The previous efforts, guidance and expertise of EPRI colleagues,

Doug Dorr, Rob Kavet, Brian Seal, are gratefully acknowledged.


Take-Home Message

EPRI Involvement in Electromagnetic Safety Issues

• EPRI conducts independent, non-profit research in the

interest of the public

• Documented, in-depth involvement in EM fields health

effects research

EPRI studies on Smart Meter EM Emissions

• Several studies with testing in actual residential

installations

• Laboratory measurements to characterize worst case

scenarios


Take-Home Message

EPRI

Approach

EPRI position within the wide range of approaches in tackling the

Smart Meter EM Emission Effects and EM Field Health Issues


Contents

1. Background: the Smart Grid

2. Issues With Smart Meters

3. Current EM Exposure Safety Standards

4. About the Electric Power Research Institute

5. EPRI Research on EM Exposure Safety

6. EPRI Research on Smart Meters Emissions

7. EM Field Primer

8. Smart Meter Emissions 2013 Project

9. Conclusions

Background: the Smart Grid



The Smart Grid Big Picture

• In a recent roadmapping publication (*), the IEC also observes that the smart grid has become more a marketing term, rather than a technical definition.

• The current technical consensus and de facto trends indicate that the current evolution of the power grid monitoring is leading toward a widespread integration of digital communication (both wired and wireless) and processing technology.

• In principle, this would allow a capillary monitoring of the grid status and the ability to perform real-time or as-needed optimization of generation, power delivery paths, and characteristics of overall end-user electrical load.

• This technology upgrade that ties together generation, distribution, and utilization is commonly referred to as “smart grid”.

(*) International Electrotechnical Commission, IEC Smart Grid Standardization Roadmap, Edition 1.0 (2010),

www.iec.ch/smartgrid/downloads/sg3_roadmap.pdf.



The Smart Grid: enhanced interaction among different components of the electric power system

• Top level: generation level, the proper response to the load variations needs to be in place

• Bottom level, utilization, the customer must be provided with a nominal level of power , dependable service, and a fast recovery from power outages

Generation

Transmission & Distribution

• Intermediate level, the transmission and

distribution infrastructure, represents the

key of ensuring this functionality

End User


Power grid evolution: new technologies and EM Compatibility issues

1900

2000 20?? Internet of (Power Grid) Things


http://www.google.com/url?sa=i&source=images&cd=&cad=rja&docid=zuj5X-WQoyVwAM&tbnid=VU_6NDSMl8oNPM:&ved=&url=http://www.eenews.net/stories/83685&ei=6oF7UsbAC8qzkAfvlYCYAw&psig=AFQjCNEkw3fhVdKqKTssIS6x9traGRfI7Q&ust=1383912298236036



The Smart Grid Big Picture

• The communication to and from the consumer level is critical for the overall planning and managing of the grid operations.

• Need: the ability to collect timely data on the end-usage levels and their patterns

• Solution: an adequate Information Technology infrastructure

– telecommunication

– data storage/processing

– data analytics

• IT infrastructure allows for “intelligent” resources management improving

– reliability

– energy efficiency

– customer satisfaction (quality of service and economy)



• Infrastructure already

designed, tested

• In many areas is

implemented and

operational

• Large number of smart

meters to operate and

communicate in a mesh-

network environment.

Picture credit: http://www.infraxinc.com/media/content/smart-metering-lg.jpg

IT Smart Grid Mesh-Network Infrastructure



IT Smart Grid Mesh-Network Infrastructure

• Smart meters “mesh network” communication:

– directly with a receiving concentrator node

– or with another smart meter present in its neighbor

• Communication path depending on the radio wave propagation

condition that may favor one connection versus another.

• Mesh network design allows for

– maximum flexibility in the deployment and installation of the

network

– high reliability for communication in both high-density urban

environments and rural, sparsely populated areas.



Smart Meters with Wireless Communication

• In the United States, the typical implementation of this network

relies on wireless communication, organized in a similar fashion

to the cellular telephone network.

• Within this large-scale picture, the smart meters—the upgraded

version of the revenue meters—represent the natural interface

with the large number of customer installations.

Picture credit: http://www.landisgyr.com



Smart Meter Radios

• The smart meters designed for this application utilize radios

operating in the high-frequency region of the radio spectrum, near

the frequencies allocated for cellular telephones.

Picture credit: http://www.lbl.gov/images/MicroWorlds/EMSpec.gif

Picture credit: www.silverspringnet.com

Issues with Smart Meters



• “Smart meters” radio emissions

(health concerns)

• Cost, benefits and drawbacks

(interface w/ smart grid, new technologies, EMC)

• Smart meters getting too smart?

(cybersecurity, privacy)

• Alternatives and future outlook

(power line communication, optical fiber, directive

antennas)

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=IX8fQVjTFflyFM&tbnid=EP8ZUQxtupq-WM:&ved=0CAUQjRw&url=http://low-carb-scams.com/tag/heath-squier/&ei=S8L2UpiANumz2QXfgIHQCQ&psig=AFQjCNHe0r6-sffxyfCU9zI55iw_dKzJ1w&ust=1391989594858810



Concerns

• EM emissions impacting human health

– Known thermal effects

– Other unspecified effects

• Proximity to living areas due to wall installation

• Not having a choice

The EPRI Approach

• All safety concerns are taken very seriously

• Unfiltered, unbiased research

• Work in the interest of the public

Current EM Exposure Safety Standards



“Guidelines for Limiting Exposure to Time-Varying Electric, Magnetic,

and Electromagnetic Fields (up to 300 GHz)”. Health Phys. 74, 494, 1998.


Current EM Exposure Safety Standards (II)

http://www.icnirp.de/documents/emfgdl.pdf



“Overall, these incidence data from the United States based on

high-quality cancer registries do not provide support for the

view that use of cellular phones causes brain cancer.”



Health Physics, 2008

“An examination of all generally accepted and proposed

mechanisms…shows that in the frequency range from

several megahertz to a few hundred gigahertz…, the

principal mechanism for biological effects, and the only

well-established mechanism, is the heating of tissues.”



Applicable Standards

• EM exposure standards

– ICNIRP

– IEEE

– FCC

Previous Investigations

• EPRI Reports

• EPRI workshop

About EPRI


About the Electric Power Research Institute

EPRI’s Focus

• Scientists and engineers working on nearly every area of electricity

generation, delivery and use, management and environmental

responsibility

Environmental

Generation

Distribution &

Utilization

Nuclear


About the Electric Power Research Institute

EPRI’s Business

• The Electric Power Research Institute, Inc. conducts research,

development and demonstration (RD&D) relating to the

generation, delivery and use of electricity for the benefit of the

public

• An independent, nonprofit organization: “To promote, engage in

and conduct research in both the pure and applied sciences for

the advancement and betterment in the public service of the

production, transmission and distribution of electric power”

[excerpt from EPRI articles of incorporation)

EPRI conducts independent, non-profit research in the interest of the

public [www.epri.com]

EPRI Research on EM Exposure Safety



http://www.epri.com/Our-Work/Pages/Health-and-Safety.aspx



EPRI Reports #1024737 and #1023105



http://mydocs.epri.com/docs/Portfolio/PDF/2013_P060.pdf

http://mydocs.epri.com/docs/Portfolio/P2014/2014_P060.pdf

EPRI Research on Smart Meters Emissions


EPRI Research on Smart Meters Emissions

Summary: EPRI Research Reports 2010-2014

• A Perspective on Radio-Frequency Exposure Associated With Residential Automatic Meter Reading,

EPRI, Palo Alto, CA: 2010.1020798.

• An Investigation of Radiofrequency Fields Associated With the Itron Smart Meter, Palo Alto, CA:

2010. 1021126.

• Radio-Frequency Exposure Levels From Smart Meters: A Case Study of One Model, EPRI, Palo

Alto, CA: 2011. 1022270.

• Characterization of Radio Frequency Emissions From Two Models of Wireless Smart Meters, EPRI,

Palo Alto, CA: 2011. 1021829.

• Program on Technology Innovation: Environmental and Health Issues Related to Radiofrequency

Emissions from Smart Grid Technologies - Summary of Two Workshops, EPRI, Palo Alto, CA: 2011.

1024737.

• EPRI Comments: A Perspective on Two Smart Meter Memoranda - EMF and RF Health Assessment

and Safety, EPRI, Palo Alto, CA: 2012. 1024952.

• Characterization of Radio Emissions from Advanced Metering Infrastructure Revenue Meters

(Smart Meters) in CPS Energy Residential Installations, EPRI, Palo Alto, CA: 2014, to be published.


EPRI Research on Smart Meter Emissions

An Investigation of Radiofrequency Fields Associated with the Itron Smart Meter, Palo Alto,

CA: 2010. 1021126.

• General discussion of Automatic Metering Infrastructure (AMI) presented as a summary white paper.

• Analysis defining

– the typical operational conditions at low duty cycles,

– the expected level of exposure in comparison with the FCC guidelines

• Comparison with EM emission from other common devices (like cellular telephones).



A Perspective on Radio-Frequency Exposure Associated With Residential Automatic Meter

Reading, EPRI, Palo Alto, CA: 2010. 1020798.

• Summary of the EPRI perspective on

smart meters

• Focus on two main research activities:

– analysis of the amount of RF energy

deposited in persons exposed to smart

meter emissions

– study of RF emissions from one

particular type of smart meter model,

under controlled conditions at the

manufacturer’s facility.



An Investigation of Radiofrequency Fields Associated with the Itron Smart Meter, Palo Alto,

CA: 2010. 1021126.

• General discussion of Automatic Metering Infrastructure (AMI) presented as a summary white paper.

• Analysis defining

– the typical operational conditions at low duty cycles,

– the expected level of exposure in comparison with the FCC guidelines

• Comparison with EM emission from other common devices (like cellular telephones).



Radio-Frequency Exposure Levels From Smart Meters: A Case Study of One Model, EPRI, Palo

Alto, CA: 2011. 1022270.

• Report on RF emission data collection on smart meters carried out in a laboratory setting and at residences in the states of California and Washington.

• Analysis of the EM emission vs. FCC standard

• Results indicate emissions always less than 1% of the FCC maximum permitted exposure (MPE) for typical duty-cycle operating conditions.

• Emissions at 100% duty cycles were measured and were found at a level less than the FCC limits.

• Indoors shielding effect from typical home construction materials reduces the field level by an additional order of magnitude compared with the one measured outdoors.



Characterization of Radio Frequency Emissions From Two Models of Wireless Smart Meters,

EPRI, Palo Alto, CA: 2011. 1021829.

• Measurements on typical indoor values of the RF fields for six residential locations in the service territory of the PG&E electric utility company.

• Measurements of the composite RF field environment from arrays of smart meters installed and operating next to each other in three different apartment complexes (including one with 112 co-located smart meters).

• Analysis of data transmissions from 88,296 smart meters, collected via the PG&E data-management system, was utilized to provide a statistical distribution of meter duty cycles to be included in the determination of time-averaged potential exposure



Program on Technology Innovation: Environmental and Health Issues Related to

Radiofrequency Emissions from Smart Grid Technologies - Summary of Two Workshops, EPRI,

Palo Alto, CA: 2011. 1024737.

• Summary of two workshops that were conducted to study the electromagnetic environments created by emerging technologies and on their potential health effects associated with radio-frequency (RF) emissions

• Conclusions indicate that there is a lack of relevant findings about “non-thermal” effects

• Open questions related to the risks from heavy cell phone use and to the consistent observation of slightly altered brain-wave activity in human subjects exposed to radio-frequency fields under laboratory conditions.



EPRI Comments: A Perspective on Two Smart Meter Memoranda - EMF and RF Health

Assessment and Safety, EPRI, Palo Alto, CA: 2012. 1024952.

• Memorandum addressing the specifics of the debate about the radio-frequency (RF) electromagnetic fields emitted from smart meters and related health risks.

• In all the reported studies, smart meters EM emission levels in typical conditions of utilization and exposure have been found well below both the thresholds from officially recognized safety standards (IEEE, FCC, and, ICNIRP)

• Smart meter emissions lower than the ones from other common sources of EM field to which the public is exposed.



Characterization of Radio Emissions from Advanced Metering Infrastructure Revenue Meters

(Smart Meters) in CPS Energy Residential Installations, EPRI, Palo Alto, CA: 2014, to be

published.

• This technical report presents the results of electromagnetic (EM) emission measurements in the radio frequency (RF) range from advanced metering infrastructure (AMI) utility meters (smart meters) employed by CPS Energy in its territory of operation.

• The study is focused on the determination of the maximum possible level of emissions, the typical population exposure conditions, and a comparative set of measurements from other (EM) sources that are present in a common household.

• The results indicate that human exposure would mostly occur at RF electric field pulses levels about 10%, or less, of international standard safety guidelines for continuous exposure.

• Smart meters emissions also compare favorably to those from other devices to which consumers are typically exposed, from power frequency to microwaves.

EM Field Primer


EM Field Primer

Relevant Characterizing Parameters

• Amplitude of Electric (E) and Magnetic field (B) components

– Why they matter: the coupling issues

– The impacts on living tissue

– Near- and Far-field

• Radiated Power vs. Reactive Power

• Frequency

– Propagation through matter

– Absorption and energy conversion

• Time of Exposure


EM Field Primer

Credit: http://hyperphysics.phy-astr.gsu.edu/hbase/waves/emwavecon.html

Electromagnetic waves

Applet: http://www.cabrillo.edu/~jmccullough/Applets/Flash/Optics/EMWave.swf

http://www.cabrillo.edu/~jmccullough/Applets/Flash/Optics/EMWave.swf

http://www.cabrillo.edu/~jmccullough/Applets/Flash/Optics/EMWave.swf


EM Field Primer

Credit: http://www-antenna.ee.titech.ac.jp/~hira/hobby/edu/em/smalldipole/smalldipole.html

Dipole antenna electric field lines Dipole antenna electric field energy

Electric and magnetic field components

• Generation

• Propagation


EM Field Primer

Measuring the EM Field

• High-frequency instruments

• Low-frequency instruments

Smart Meter Emissions 2013 Project


Characterization of Radio Emissions from Advanced Metering

Infrastructure Revenue Meters (Smart Meters) in CPS Energy

Residential Installations

• Three different smart meter models currently utilized or planned

for installation in the CPS Energy service territory in San

Antonio, Texas

• Measure the EM emissions generated by the radio transmitter

installed to provide two-way communication capabilities.

• Obtain an accurate characterization of these emissions

• Provide a relative term of comparison with other common

sources of EM fields to which the public is exposed.




Project Scope

• Focus on characterization of smart meter emissions in actual and

planned residential installations

• The study not focused on actual impact of EM fields on the

human body, or on biologic material in general,

• Safety-related considerations relying on internationally

recognized and most stringent guidelines for human exposure to

EM fields from the International Commission on Non-Ionizing

Radiation Protection (ICNIRP).


Characterization of Radio Emissions from Advanced

Metering Infrastructure Revenue Meters (Smart Meters) in

CPS Energy Residential Installations

• Three different smart meter models currently utilized or

planned for installation in the CPS Energy service territory

in San Antonio, Texas

• Measure the EM emissions generated by the radio

transmitter installed to provide two-way communication

capabilities.

• Obtain an accurate characterization of these emissions

• Provide a relative term of comparison with other common

sources of EM fields to which the public is exposed.




Project Scope

• Focus on characterization of smart meter emissions in

actual and planned residential installations

• The study not focused on actual impact of EM fields

on the human body, or on biologic material in

general,

• Safety-related considerations relying on

internationally recognized and most stringent

guidelines for human exposure to EM fields from the

International Commission on Non-Ionizing Radiation

Protection (ICNIRP).


Project Highlights

• Project with high general relevance in the context of current AMI

technology development

• Data have been collected with a particular focus on actual utility

installation

• Measurements performed on smart meters in operating residential

installations

• More extensive laboratory tests were conducted to cover different

models that are currently in the utility smart meter installation

plan



Vertical Direction (y)

Pictorial representation of the measurements data for the worst-case (continuous transmission) scenario of

EM emissions in the radio-frequency range from the tested smart meters. The field level is shown compared

to the maximum permitted exposure (MPE) as defined in the ICNIRP international standard



Exposure

Time (s)

% ICNIRP Limit

(Peak EM field, typical usage)

0.1 1 10 100 1000 10000

100

10

1

Qualitative comparison of EM emissions for different sources present in common

households vs. typical exposure time (both axes are on a logarithmic scale).





Reference Electric Fields - Basis of Estimate

•




Following the Proper Procedure

• Cross-correlation time domain and frequency domain

• Verification of measurements vs. theory

– Field level from TX power and antenna pattern

– Field trend vs. distance

• Near-field vs. far-field effects

• Consistency with previous reports

• Error analysis

Low-accuracy Requirements

• Safety guidelines are…just guidelines, not precise limits

• Large margin to include worst case scenarios

Can We Trust the Numbers?

Conclusions


Conclusions

Results from EPRI 2013 project consistent w/previous research

• For any possible exposure conditions smart meter EM field always less than the maximum permitted exposure (MPE) levels specified by the ICNIRP safety standard.

• This comparison holds in the most unfavorable conditions where the pulsed emission level is compared with the level allowed for a continued exposure over a period of six minutes.

• For typical consumer exposure in residential operating conditions, are one order of magnitude less, or lower, than the ICNIRP MPE (results are also consistent with previous studies)

• Smart meters generate the lowest EM emissions in terms of combined exposure time and field intensity when compared to common devices that generate EM fields.

Together…Shaping the Future of Electricity

Backup Slides


Rationale for a Power Utility EMC Program

Electric grid rapid technology transition

• Closer integration of power and control

electronics, data processing, and

telecommunication technologies.

Increasingly complex EM environment

• Large current and voltage components,

sensitive electronics, digital signals, and

analog waveforms all coexist and interact.

A new environment for the electric power grid


Smart Meters, Smart Grid and EMC

EMC improves PQ

• EMC-conscious design and testing of power grid

components, less disturbances, outages, improving PQ

Smarter Grid, more EMC

• Fully integrated Smart Grid: co-existence of power

lines, sensors, data communication and processing, all

requiring stricter EMC guidelines

Ya’ll need EMC anyway

• EMC fixes are generally more costly and less effective

than preventive design and testing

The Need for EMC


Relationship between EMC to PQ

EMC Events

• Typically involving small, stray signals coupling to sensitive

equipment

PQ Events

• Typically manifest themselves on the power lines/systems

• Require compatible power levels to be generated

PQ relates to the perturbation of a power system and that typically

requires another power system


EMC New Role in an Old Engineering Sector

The Power Utility New Look

• Ubiquitous spreading of control electronics, sensors and data communication channels creates a new level of electromagnetic vulnerability

• Similarly to what happened in Aerospace and Defense: final goal of the EMC integration in the electric power industry would be the creation of an “EMC Standard for the Electric Utility”

• Including the relevant aspects of Smart Grid technology


• Basic scenario: a conductor is energized with a

given AC potential with the respect to ground

• Equivalence to a monopole antenna and, by image

theory, to a dipole antenna

Energized Objects

VAC

L

Ideal Conductor

L

L

Ground plane

Monopole Antenna Dipole Antenna


The Near-Field Region

• An antenna with length L much smaller than the wavelength

l is referred to as “electrically short” (typically L<< l /50)

• The EM emission pattern of electrically short antennas is

much like that of an infinitesimal (ideal) dipole

• For an ideal dipole the maximum radiated and reactive

powers are the equal at a distance R=l/2p

• The boundary r<R defines the near field region. The far field

region is considered for r>>R. A transition region is defined

for r>R but still not r>>R (there is no sharp transition in

between any of these regions)


Electric field lines of force generated in a small dipole

The Electric Field from a Dipole

t=0

+

_

_

+

t=T/2

VAC

+ _

t=T: field lines that were

generated in t=0 are forced to

close

+

_

Documents

Smart Metering Issues - Midwest Rural Energy Council · PDF fileSmart Metering Issues ... A Perspective on Radio-Frequency Exposure Associated With Residential Automatic Meter Reading,